Hot water pipes and fittings must be able to withstand prolonged exposure to high temperatures and pressures, as well as fluctuations in temperature and pressure. They must also resist failure when exposed to cycles of fluctuating loads or stresses associated with the pressure shocks resulting from opening and closing taps (the so-called “water hammer effect”) and the temperature variations associated with flow of warm water into a cold fitting or cold water into a warm fitting. Historically, copper metal has been the material most commonly used for hot water pipes and fittings. Recently, certain plastics, such as polysulfones and polyethersulfones, have also been used for hot water pipes and fittings, but these plastic materials are quite expensive relative to other plastics. There is therefore a need for less expensive plastic materials that exhibit the range of properties required for use in hot water fittings and pipes.